Abstract: Aspects of the invention are directed to a method for forming a graphene composite structure. Initially, an encapsulating film is formed on a substrate. The encapsulating film comprises graphene. Subsequently, a plurality of particles are deposited on the encapsulating film, and then a temporary layer is deposited on the plurality of active particles and the encapsulating film. The substrate is then removed. Lastly, the temporary layer is also removed so as to cause the plurality of particles to form a cluster that is at least partially encapsulated by the encapsulating film.